Methods for imparting a desired style to hair and retaining it can be broadly classified into: a surface reformation method comprising allowing a hair styling component to remain on the surface of hair; and an internal reformation method comprising penetrating a hair styling component into the inside of hair. The former method is characterized in that it easily provides high hair styling properties, but it tends to provide unnatural hand feeling. On the other hand, the latter method is characterized in that it hardly provides sufficient hair styling properties, but it tends to provide natural hand feeling.
As a result of the recent trend in hairstyle, preference for natural hairstyle that is not too elaborated and good hand feeling has increased. In such background, it has been desired to develop a technique of reforming the inside of hair that provides higher hair styling effects, while keeping natural hand feeling and/or finishing.
As a technique of improving hair styling properties by reforming the inside of hair, a technique of reforming the inside of hair by allowing sugar, amino acid, enzyme or the like to penetrate into hair has been known (Patent Literatures 1 and 2). Also, it has been reported that polyglycerin having a specific molecular weight or a specific polymerization degree has excellent hair styling properties, although it has not been suggested that such polyglycerin has an internal reforming effect (Patent Literatures 3 and 4).
Moreover, in recent years, there has been a trend in which hair color is changed by a color-treatment for fashion, or hair style is changed by an entire or partial perm treatment. As a result, hair is largely damaged by such chemical treatments or daily hair washing. Under such circumstances, a hair styling agent, in which a conditioning component is combined with a glycerin derivative, has been proposed (Patent Literature 5).